mac80211: Consolidate mesh path duplicated functions
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/mesh_pathtbl.c b/net/mac80211/mesh_pathtbl.c
index 7797f55..a66a2ca 100644
--- a/net/mac80211/mesh_pathtbl.c
+++ b/net/mac80211/mesh_pathtbl.c
@@ -48,10 +48,10 @@
int mesh_paths_generation;
/* This lock will have the grow table function as writer and add / delete nodes
- * as readers. When reading the table (i.e. doing lookups) we are well protected
- * by RCU. We need to take this lock when modying the number of buckets
- * on one of the path tables but we don't need to if adding or removing mpaths
- * from hash buckets.
+ * as readers. RCU provides sufficient protection only when reading the table
+ * (i.e. doing lookups). Adding or adding or removing nodes requires we take
+ * the read lock or we risk operating on an old table. The write lock is only
+ * needed when modifying the number of buckets a table.
*/
static DEFINE_RWLOCK(pathtbl_resize_lock);
@@ -335,25 +335,14 @@
}
-/**
- * mesh_path_lookup - look up a path in the mesh path table
- * @dst: hardware address (ETH_ALEN length) of destination
- * @sdata: local subif
- *
- * Returns: pointer to the mesh path structure, or NULL if not found
- *
- * Locking: must be called within a read rcu section.
- */
-struct mesh_path *mesh_path_lookup(u8 *dst, struct ieee80211_sub_if_data *sdata)
+static struct mesh_path *path_lookup(struct mesh_table *tbl, u8 *dst,
+ struct ieee80211_sub_if_data *sdata)
{
struct mesh_path *mpath;
struct hlist_node *n;
struct hlist_head *bucket;
- struct mesh_table *tbl;
struct mpath_node *node;
- tbl = rcu_dereference(mesh_paths);
-
bucket = &tbl->hash_buckets[mesh_table_hash(dst, sdata, tbl)];
hlist_for_each_entry_rcu(node, n, bucket, list) {
mpath = node->mpath;
@@ -370,30 +359,23 @@
return NULL;
}
+/**
+ * mesh_path_lookup - look up a path in the mesh path table
+ * @dst: hardware address (ETH_ALEN length) of destination
+ * @sdata: local subif
+ *
+ * Returns: pointer to the mesh path structure, or NULL if not found
+ *
+ * Locking: must be called within a read rcu section.
+ */
+struct mesh_path *mesh_path_lookup(u8 *dst, struct ieee80211_sub_if_data *sdata)
+{
+ return path_lookup(rcu_dereference(mesh_paths), dst, sdata);
+}
+
struct mesh_path *mpp_path_lookup(u8 *dst, struct ieee80211_sub_if_data *sdata)
{
- struct mesh_path *mpath;
- struct hlist_node *n;
- struct hlist_head *bucket;
- struct mesh_table *tbl;
- struct mpath_node *node;
-
- tbl = rcu_dereference(mpp_paths);
-
- bucket = &tbl->hash_buckets[mesh_table_hash(dst, sdata, tbl)];
- hlist_for_each_entry_rcu(node, n, bucket, list) {
- mpath = node->mpath;
- if (mpath->sdata == sdata &&
- memcmp(dst, mpath->dst, ETH_ALEN) == 0) {
- if (MPATH_EXPIRED(mpath)) {
- spin_lock_bh(&mpath->state_lock);
- mpath->flags &= ~MESH_PATH_ACTIVE;
- spin_unlock_bh(&mpath->state_lock);
- }
- return mpath;
- }
- }
- return NULL;
+ return path_lookup(rcu_dereference(mpp_paths), dst, sdata);
}
@@ -836,7 +818,8 @@
int i;
rcu_read_lock();
- tbl = rcu_dereference(mesh_paths);
+ read_lock_bh(&pathtbl_resize_lock);
+ tbl = resize_dereference_mesh_paths();
for_each_mesh_entry(tbl, p, node, i) {
mpath = node->mpath;
if (rcu_dereference(mpath->next_hop) == sta) {
@@ -845,6 +828,7 @@
spin_unlock_bh(&tbl->hashwlock[i]);
}
}
+ read_unlock_bh(&pathtbl_resize_lock);
rcu_read_unlock();
}
@@ -880,10 +864,12 @@
struct mesh_table *tbl;
rcu_read_lock();
- tbl = rcu_dereference(mesh_paths);
+ read_lock_bh(&pathtbl_resize_lock);
+ tbl = resize_dereference_mesh_paths();
table_flush_by_iface(tbl, sdata);
- tbl = rcu_dereference(mpp_paths);
+ tbl = resize_dereference_mpp_paths();
table_flush_by_iface(tbl, sdata);
+ read_unlock_bh(&pathtbl_resize_lock);
rcu_read_unlock();
}